Chapter Two:
Environmental Measurements

This chapter reviews U.S. ambient-air-quality standards and recommended limits for chemical hazards, as well as environmental measurements available for the Gulf region before, during, and after the Kuwait oil well fires. This chapter describes the concentration levels of pollutants measured during the oil fires, shows the consistency of these measurements across studies, and compares their magnitude to U.S. ambient air and occupational standards. This chapter provides the necessary background for this to be the stand-alone report described in the introduction. It is an overview and in no way presumes to be either a critical or comprehensive analysis and evaluation of all the environmental data. For a more detailed discussion of the environmental data presented in the following tables, refer to the source references. The target audience for the present chapter, as mentioned above, is the scientific community familiar with the issues, methodologies, and processes that are the basic tools of environmental health science.

The magnitude of the fires and the extensive publicity about the amount of smoke sparked concern around the world regarding effects on global processes such as ozone depletion, acid rain, global warming, and other atmospheric phenomena. For example, some worried that the smoke could disrupt the monsoon season in southern Asia and trigger a drought affecting crops in India and Pakistan (Horgan, 1991a).

Although no global effects were noted, the passage of the smoke was detected worldwide where very sensitive equipment was located. Beginning in February 1991, the National Oceanic and Atmospheric Administration (NOAA) recorded numerous "soot spikes" in air-sampling data at its observatory located 4000m above sea level in Hawaii. Wind-pattern records indicate that the sooty air had left the Persian Gulf 7-10 days earlier. The March levels at Mauna Loa were five times higher than during March in the previous three years; these levels were still low enough to pose negligible health risks. No global disaster occurred, as some predicted immediately after the fires began (Horgan, 1991a, 1991b).

Firefighters started to cap the flaming oil wells in April, expecting that they would need up to two years to extinguish all fires. In the meantime, a coordinated international research effort began in the spring of 1991 to assess the impact of the fires on health and the environment.

U.S. Standards and Recommendations

The 1970 Clean Air Act mandates the U.S. Environmental Protection Agency (EPA) to promulgate standards and risk assessments for the chemicals that, above certain exposure levels, may generate health risks for the general population. The standards focus on the pollutants' toxicity, including carcinogenicity, and on estimated release volumes. A small number of pollutants, called Criteria Pollutants, are ubiquitous in the United States, i.e., most people are exposed to them daily, and extensive research into their health effects has been accumulated. The Clean Air Act requires the EPA to: (1) review public health standards for six major air pollutants (the Criteria Pollutants) every five years (2) update the standards, if necessary, to "protect public health with an adequate margin of safety," based on the latest, best-available science (3) consider only the public health, and not the cost of compliance, when setting the air-quality standards, and save cost considerations for the implementation phase. The Criteria Pollutants are ozone (O3); particulate matter of less than 10 micrometers in diameter (PM10) and of less than 2.5 micrometers in diameter (PM2.5); carbon monoxide (CO); nitrogen dioxide (NO2); lead (Pb); and sulfur dioxide (SO2). The data on these pollutants are integrated by the EPA to set a National Ambient Air Quality Standard (NAAQS) for each criteria pollutant. These standards are listed in Table 2.1.

Table 2.1
Federal Ambient Air Quality Standards

Pollutant Averaging Time Concentration
Ozone (O3) 8 hour 0.080 ppm (160 µg/m3)
Particulate Matter
PM10 Annual mean 50 µg/m3
24 hour 150 µg/m3
PM2.5 Annual mean 15 µg/m3
24 hour 65 µg/m3
Carbon Monoxide (CO) 8 hour 9 ppm (10 µg/m3)
1 hour 35 ppm (40 µg/m3)
Nitrogen Dioxide (NO2) Annual mean 0.053 ppm (100 µg/m3)
Lead (Pb) Calendar quarter 1.5 µg/m3
Sulfur Dioxide (SO2) Annual mean 0.030 ppm (80 µg/m3)
24 hour 0.14 ppm (365 µg/m3)

The Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) requires that the Agency for Toxic Substances and Disease Registry (ATSDR) develop jointly with the EPA a list of the most common hazardous substances and prepare a toxicological profile for each substance. The ATSDR Minimal Risk Levels (MRL) were developed as the response to this mandate. An MRL is an estimate of the daily human exposure to a hazardous substance that is likely to be without appreciable risk of adverse noncancer health effects over the specified exposure duration. MRLs are generally based on the most sensitive substance-induced end point considered to be of relevance to humans (ATSDR, 1997). Table 2.2 lists the available MRLs for the pollutants of concern.

Table 2.2
ATSDR Minimal Risk Levels for Hazardous Substances

Substance Duration Concentration Endpoint
Benzene Acute 0.5 ppm (1600µg/m3) Immunological
Toluene Acute 3 ppm (11,500 µg/m3) Neurological
Chronic 1 ppm (3800 µg/m3) Neurological
Xylene Acute 1 ppm (4400 µg/m3) Neurological
Intermediate 0.7 ppm (3100 µg/m3) Developmental
Chronic 0.1 ppm (440 µg/m3) Neurological
Cadmium Chronic 0.2 µg/m3 Renal
Chromium (III) Intermediate 0.02 µg/m3 Respiratory
Chronic 0.02 µg/m3 Respiratory
Mercury Acute 0.02 µg/m3 Developmental
Chronic 0.014 µg/m3 Neurological
Nickel Intermediate 0.1 µg/m3 Respiratory
Vanadium Acute 0.2 µg/m3 Respiratory


The National Institute for Occupational Safety and Health (NIOSH) was established by the Occupational Safety and Health Act of 1970 as part of the Centers for Disease Control (CDC). One of NIOSH's mandates is to recommend criteria for preventing disease and hazardous conditions in the workplace. NIOSH develops and periodically revises recommended exposure limits--i.e., time-weighted average concentrations (TWAs)--for hazardous substances by evaluating all available medical, biological, and other relevant information. These recommendations are transmitted to the Occupational Safety and Health Administration (OSHA) and the Mine Safety and Health Administration for use in promulgating legal standards. NIOSH's TWA standards are the maximum recommended exposures in the workplace for up to a 10-hour workday during a 40-hour workweek. OSHA's TWA concentrations must not be exceeded during any 8-hour workshift of a 40-hour workweek.

The American Conference of Governmental Industrial Hygienists (ACGIH), a professional society--not a government agency--devoted to the administrative and technical aspects of occupational and environmental health, develops Threshold Limit Values (TLVs) as recommendations or guidelines for use in the practice of industrial hygiene in the workplace. TLVs are TWA concentrations that should not be exceeded during any 8-hour workshift of a 40-hour workweek. All these concentration limits are set at levels believed to be without adverse effects for nearly all workers during repeated daily exposure. Table 2.3 lists NIOSH, OSHA, and ACGIH recommended occupational limits for the noted pollutants.

Table 2.3

NIOSH, OSHA, and ACGIH Occupational Limits
for the Pollutants of Interest
Pollutant Symbol NIOSHb OSHAb ACGIHb
Ozone O3 200 200 100
Sulfur dioxide SO2 5000 13,000 5200
Nitrogen dioxide NO2 1800c 9000c 5600
Nitric oxide NO 5000 5000 31,000
Acenaphthenea 100 200 200
Benzo(a) anthracenea 100 200 200
Biphenyla 100 200 200
Chrysenea 100 200 200
Fluoranthenea 100 200 200
Phenanthrenea 100 200 200
Pyrenea 100 200 200
Particulate PM10 NA NA 3000d
Cadmium Cd NA 5 10
Chromium Cr 500 500 500
Nickel Ni NA 1000 120
Lead Pb 100 50 50
Vanadium V 50 50 50
Zinc Zn 1000 1000 500
Benzene 320 3200 1600
Toluene 750,000 375,000 188,000
Ethyl benzene 435,000 435,000 435,000
m,p-Xylene 435,000 435,000 435,000
o-Xylene 435,000 435,000 435,000

SOURCES: NIOSH, 1997; ACGIH, 1997.

NOTE: NA = Not applicable.

aComponents of coal tar pitch volatiles.
bConcentration limits are for their respective TWAs except for NO 2.
cShort-term exposure limit, a 15-minute TWA.
dPM10 not otherwise regulated.

Since the EPA's standards are set to protect the general population--including those most vulnerable, such as small children, the elderly, and people with respiratory and other diseases--from increased health risks due to exposures to ambient pollutants, they are much lower than occupational standards (e.g., ACGIH, NIOSH, and OSHA), and they include a margin of safety.

As discussed above, in the United States there are different standards of acceptable levels of contaminants set according to which population needs to be protected. The EPA's NAAQS, for the ubiquitous criteria pollutants, are targeted for the general population for continuous ambient exposures. ATSDR-MRLs give the concentrations of hazardous substances that will likely not affect the general population through daily exposure. NIOSH, OSHA, and ACGIH standards are for occupational exposures during 40-hour workweeks lasting the worker's lifetime.

The armed forces deployed to the Gulf theater are a unique segment of the population. They are predominately young (18-40), fit, and healthy. They stayed in the region after the onset of the Kuwait oil fires for (at most) 6-8 months. There are no studies in the scientific literature that focus on the possible health effects due to exposures to contaminants in this population segment. What standards should be considered appropriate for this group, exposed for 24 hours over a limited period of time? The NAAQS and MRL ambient levels are unrealistic because of the margins of safety included to protect the most vulnerable members of the population. The NIOSH, OSHA, and ACGIH occupational standards, although seemingly more appropriate, assume a step-function exposure with periods of low levels in-between but lasting for many years. Perhaps the occupational standards combined with an empirical factor to account for the continuous exposure would give a reasonable exposure-limit estimate.

Measurements Taken Before the Oil Well Fires

Scant environmental data from the region exist to use as a baseline. Outdoor NO and NO2 concentrations were measured at three sites in the city of Riyadh, Saudi Arabia (the Hitachi Building, at Al Matar Street; Al-Khazzan Street, one block from Makkah Road; King Saud University, Department of Civil Engineering), in 1986 and 1987. Table 2.4 illustrates the measurements from Al-Khazzan Street in 1987 (the location with the highest concentrations), and compares them with the NAAQS, the EPA standard, and the NIOSH occupational TWA values standards. The outdoor NO and NO2 concentrations respectively are at least 270 and 14 times the reported average worldwide. Most of the outdoor NO and NO2 in Riyadh was attributed to the 1,700,000 cars registered in 1984, in an area about 1900 km2 with a population of 1,600,000 (Rowe, 1991).

Table 2.4
NO and NO2 Concentrations in Riyadh, Saudi Arabia, in 1987

Riyadh Concentration EPA--NAAQS Ambient Standard ACGIH-Occupational Standard
Peak 9.2 1.48
Maximum average hourly 2.7 0.16
Maximum average daily 2.0 0.05
Overall sampling average 0.86 0.040 NA 0.053 25 3.0

SOURCE: Rowe, 1991.
NOTE: NA = not applicable.

Concentrations of NO2 were measured throughout the state of Bahrain from January 6 to January 29, 1991, at the onset of the Persian Gulf War and before the burning of the oil wells. A large number (approximately 100,000) of jet flights took place during that period. The highest NO2 levels were concentrated in Manama, the capital, with weekly mean values up to 0.145 ppm (273 µg/m3), while the lowest were in coastal villages, which had means around 0.028 ppm (53 µg/m3). Industrial areas had lower levels than the urban areas, which is characteristic where high traffic densities are the main source of NO2 (Danish and Madany, 1992).

Even though only limited environmental data are available, high particulate levels have been documented throughout the Persian Gulf region: 5080 µg/m3 in Riyadh, Saudi Arabia in 1982; 630 µg/m3 in Kuwait in 1983; and 674 µg/m3 in Bahrain in 1987 (Madany and Raveendran, 1992). A study from Dhahran, Saudi Arabia, reports TSP[1] measurements for 100 days from November 1980 to March 1981. The average maximum daily value for the period was 737 µg/m3, and the geometric mean for the period was 339 µg/m3. But when the Shammal winds were blowing, peak daily concentrations reached the extraordinary values of 2923 µg/m3 (Khattak, 1982). These values are about 20 times the 24-hour U.S. ambient standard for PM10 of 150 µg/m3. The daily variability in PM10 concentration is illustrated in Figure 4.2 for Doha, Kuwait, from June to December 1991.

Measurements Taken During the Oil Well Fires

No systematic environmental monitoring occurred in the Gulf region from the initial deployment in 1990 until May 1991. Several independent teams went to Kuwait to assess the ambient air contamination due to emissions produced by the oil well fires. Measurements began in March 1991 when most of the fires were still burning. The most extensive measurement campaign was undertaken by the U.S. Army Environmental Health Agency (USAEHA) from May to December 1991. Other groups, like the EPA Team (Hunt, 1993), sampled for short periods; these provided only snapshots of the pollution levels, but they are still useful measurements for validating the more comprehensive data obtained by USAEHA.

May 6-June 12 Measurements

Airborne measurements of the oil-fire smoke were acquired by flights through the plumes from May 6 to June 12, 1991, while about 500 oil wells were still burning (Ferek, 1992). These measurements were taken from individual plumes (black and white), from composite plumes, and superplumes that originated from different fields as well as from a small number of pool fires. Table 2.5 summarizes the mean concentrations measured. In general, soot, salt, and sulfate account for about two-thirds of the total mass of smoke particles with diameters < 3.5 µm.[2] Since data on only a few plumes were obtained, these results represent only a small portion of the entire episode; nevertheless, they are valuable additions to the body of information.

Table 2.5
Mean Concentrations of Major Gases and Particulates from Different Types of Smoke Plumes from the Kuwait Oil Fires (in µg /m3)

Plume Type & Date Sampled (1991) CO2 TOCa CO Soot (Elemental carbon) CH4 SO2 NOx Particles < 3.5 µm Diameter Saltsc
Super-composite plume (160 km downwind from Kuwait City) May 28 10,313
215 4 241 50.5
Composite plume from Greater Burgan field (20 km downwind of fires) June 12 29,143 (95.1) 915
423 25 910 2819
Individual black plume (in Umm Qudair field) June 9 8,107
455 4 166 4.9
Individual white plume (in north field) June 8 35,893
1041 29 1,093 880
From a pool fire (in Minagish field) June 2 15,536
1326 16 790 0.8

SOURCE: Ferek, 1992.

aTOC = Total nonmethane organic carbon in the vapor phase.
bPercentage of carbon specie contributing to the total carbon in the plume is included in the parentheses. It indicates combustion efficiency; a higher percentage means more efficient combustion.
cSalts = Sum of all salts measured.

July-August Measurements

A study sponsored by the National Aeronautics and Space Administration (NASA) and the EPA consisted of plume and ground-level sampling. They measured the gas and particulate composition of the plumes and endeavored to assess their effect on the air quality in Kuwait City, in the region, and across the globe. This study was carried out during July and August 1991, when about half the fires were still burning.

The ground-level sampling in Kuwait City was taken during an abrupt change in weather conditions on August 7. Until August 5, winds with speeds of 35-55 km/hr (10-15 m/sec) transported the smoke from the oil fields toward the Persian Gulf, with little visual evidence of a plume across Kuwait City. On August 5, a strong, low-lying inversion developed, winds calmed, and visibility declined sharply. Winds then returned from the northwest, and, by August 9, dispersed the material that had accumulated over the city.

In the August 7 sample, the dominant component was sand dust. Sulfur, as SO2, increased by about 50 percent during the inversion. Concentrations of Cl, Pb, Br, and Zn increased at least ten-fold. The ratio of Pb to Br of about three remained constant throughout the sampling, suggesting that their primary source was local automotive traffic and not the oil well fires. Concentrations of Ca, K, Ti, Fe, and Mn increased by less than 50 percent during the inversion period. The ratios of Si, Fe, K, Ti, and Mn to Al were within 30 percent of the values for local desert soils and similar to soils in Arizona. PAH levels in Kuwait City were typically less than 0.001 µg/m3 as shown in Table 2.11 (Stevens et al., 1993).

July 31-August 4 Measurements

A five-day study was performed in Bahrain from July 31 to August 4, 1991, collecting particulate matter (PM10) that was also analyzed for 31 polycyclic aromatic compounds (PAH), nickel, and vanadium (Madany, 1992). During the data-acquisition period, temperatures ranged from 35o to 38oC; winds ranged from 11 to 31 km/hr; the height of the inversion layer ranged from 457 to 914 m; the air was smoky; and all sampling filters appeared black.

The daily PM10 concentrations ranged from 139 to 673 µg/m3 but, although quite high, cannot be attributed only to the oil fires. Comparison with available data on particulate matter from before the Gulf War shows that these levels are common for the region.

The mean daily concentrations of Ni and V ranged from 7 to 42 ng/m3 and 11 to 42 ng/m3, respectively. They were strongly correlated, indicating that they had a common source: the oil fires (Madany, 1992).

Table 2.6 depicts the average concentrations of individual components of the PAHs in Bahrain for the study period as well as what is considered background, rural, and urban values for cities around the world for comparison (Madany, 1992). It is important to note that the PAH levels in Bahrain, which is downwind from Kuwait, were at least an order of magnitude lower than the European cities with high PAH concentrations.

Table 2.6
Levels of PAHs Measured in Bahrain and Other Sites (ng/m3)

Compound Alaska Lake Superior Netherlands Greece Berlin San Francisco Bahrain
Background Rural Urban Urban Urban
Anthracene 0.01 0.01 0.9 5.4 NA NA NA 0.04
Fluoranthene 0.16 0.10 11.0 39.0 3.6 33.0 NA 0.09
Benzo(a)anthracene NA NA 0.5 1.3 3.6 NA NA 0.07
Crysene 0.04 0.06 1.5 3.1 3.7 NA NA 0.20
Benzo(k)fluoranthene NA NA 0.5 0.7 NA 4.2 0.2 0.14
Benzo(a)pyrene 0.02 0.04 0.5 0.6 6.7 9.1 0.4 0.62
Benzo(g,h,i)perylene 0.04 0.04 0.9 1.2 8.0 11.0 1.4 0.85
Ideno(1,2,3-cd)pyrene NA NA 0.8 1.0 NA 8.2 NA 0.59

SOURCE: Madany, 1992.

NOTE: NA = not available.

A study on a "positive" aspect of the Kuwait oil fires looked into the comfort of the residents of Jubail, Saudi Arabia, during the Kuwait oil fires. Many Jubail residents said that it had been noticeably cooler since the fires were ignited in Kuwait. Some residents speculated that temperatures were 10o to 20oC below normal. Comparison of the mean air temperatures for the months of May and June 1991 with historical data for the same months indicates that the actual decrease in temperatures was not statistically significant. On the other hand, the mean temperatures for January to April were slightly higher than those predicted from historical data. Solar radiation data indicate a 26-36 percent decrease compared to the same months during 1979-1990. According to one researcher (Riley, 1992), "One way of looking at these results is to think of the smoke plumes as being analogous to the shade of an extended palm grove. The air temperature in the shade is the same as in full sunlight, but the level of human comfort is significantly higher under the trees because the solar-radiation load on an individual is reduced." This is an example of how the general population's perception of an effect can lead to a wrong conclusion.

USAEHA Environmental Measurements, May-December

The USAEHA, renamed the U.S. Army Center for Health Promotion and Preventive Medicine (CHPPM) in 1991, was commissioned to determine whether dangerous levels of pollutants from oil-fire emissions were present in U.S. troop locations. Also, in accordance with Public Law 102-190, CHPPM was to determine the potential health risks to DoD personnel deployed in Operation Desert Storm from exposures to those pollutants. Environmental monitoring began on May 15, 1991, and continued until December 3, 1991, with about 4000 samples collected. When data collection began, 558 oil wells were burning--only 8 percent of the fires had been extinguished. The last fire was extinguished on November 6, 1991.

Permanent ambient air monitoring stations were established at four locations in Saudi Arabia and six in Kuwait, although two in Kuwait had to be abandoned quickly due to logistical difficulties (see Figures 2.1 and 2.2). The sites selected were locations where large concentrations of U.S. troops and DoD civilians were stationed for long periods of time. The two mostly civilian sites were the U.S. Embassy in Kuwait and the Al Ahmadi Hospital; the others were mostly military sites.

Figure 2.1--Monitoring Sites in Kuwait

Figure 2.2--Monitoring Sites in Saudi Arabia

Based on the hazardous substances to be monitored--crude oil, by-products of incomplete combustion, breakdown products--scientists from USAEHA de-cided on a list of pollutants of concern that needed to be monitored in the Gulf region affected by the oil well fires (Table 2.7).

Table 2.7
List of the Pollutants Monitored by USAEHA

Volatile Organic Compounds (VOC)
Benzene o-Xylene Heptane
Toluene p-Xylene
m-Xylene Ethyl benzene
Polycyclic Aromatic Hydrocarbons (PAH)
Acenaphthene Benzo (g,h,i) perylene Ideno(1,2,3 -cd)pyrene
Acenaphthylene Biphenyls Methylnaphthalene
Anthracene Carbazole Naphthalene
Benzo(a)anthracene Chrysene Phenanthrene
Benzo(a)pyrene Cumene Pyrene
Benzo(b)fluoranthene Dibenzo(a,h)anthracene 1-Methylnaphthalene
Benzo(e)pyrene Dibenzofurans 2,6-Dimethylnaphthalene
Benzo(f)fluoranthene Fluoranthene 2-Methylnaphthalene
Acidic Gases
Hydrochloric acid Nitric acid Sulfuric acid
Criteria Pollutant Gases
Nitrogen dioxide Nitric oxide Ozone
Sulfur dioxide
Particulates and Metals
PM10 Nitrates Sulfates
Aluminum Chlorine Mercury
Arsenic Chromium Nickel
Beryllium Iron Sodium
Cadmium Lead Vanadium
Calcium Magnesium Zinc


Soil Sampling. Soil sampling was also performed at the air sites. There were no consistent increases in soil metals concentrations above background, except for lead. Lead increased at all sites, as it did in the air data, probably reflecting an increase in vehicular traffic and subsequent lead emissions from local gasoline. There were no VOC or PAH levels above the instrumental detection limit. There also was no detection of Cr(VI) in 76 samples analyzed with a detection limit of 100 ppb (USAEHA, 1994).

Air Sampling. The USAEHA sampling campaign measured little change in the general air quality during the monitoring period. Table 2.8 lists the highest mean values of the contaminants listed in Table 2.7 as measured by the USAEHA during their 1991 campaign. Although considerable increases were noted in particulate matter, these concentrations were considered to be within the range common to this area.

Table 2.8
Mean Concentrations of Air Pollutants of Concern in May-December 1991

Pollutant Location Mean [c]a ACGIH's TLVs
Ozone O3 Riyadh 53.4 µg/m3 100c µg/m3
Sulfur dioxide SO2 Riyadh 23.8 µg/m3 5200 µg/m3
Nitrogen dioxide NO2 Khobar 58.5 µg/m3 5600 µg/m3
Nitric oxide NO Khobar 24.2 µg/m3 31,000 µg/m3
Acenaphtheneb Eskan Village 0.62 ng/m3 200,000 ng/m3
Benzo(a)anthraceneb Eskan Village 0.60 ng/m3 200,000 ng/m3
Biphenylb Eskan Village 7.20 ng/m3 200,000 ng/m3
Chryseneb Eskan Village 0.48 ng/m3 200,000 ng/m3
Fluorantheneb Eskan Village 1.41 ng/m3 200,000 ng/m3
Phenanthreneb Ahmadi 0.48 ng/m3 200,000 ng/m3
Pyreneb Eskan Village 0.65 ng/m3 200,000 ng/m3
Particulate PM10 Ahmadi 354 µg/m3 3000d µg/m3
Cadmium Cd Camp 1 0.003 µg/m3 10 µg/m3
Chromium III Cr Camp 1 0.027 µg/m3 500 µg/m3
Nickel Ni U.S. Embassy 0.052 µg/m3 120 µg/m3
Lead Pb Eskan Village 0.675 µg/m3 50 µg/m3
Vanadium V Ahmadi 0.028 µg/m3 50 µg/m3
Zinc Zn Camp 1 0.068 µg/m3 500 µg/m3
Benzene Ahmadi 7.82 µg/m3 1600 µg/m3
Toluene Ahmadi 21.8 µg/m3 188,000 µg/m3
Ethyl benzene Ahmadi 14.7 µg/m3 435,000 µg/m3
m,p-Xylene Ahmadi 40.5 µg/m3 435,000 µg/m3
0-Xylene Ahmadi 12.8 µg/m3 435,000 µg/m3

NOTES: NA: Standard or recommended concentration not available.

aUSAEHA, 1994.
bThere were only a few samples above the detection limit.
cTLV performing heavy work.
dPM10 not otherwise regulated.

Exposures to several VOCs (i.e., benzene, toluene, ethyl-benzene, and xylene) were similar to levels observed in cities with major petrochemical industries (i.e., Houston and Philadelphia (USAEHA, 1994)). Figure 2.3 compares median VOC concentrations in Kuwait, Saudi Arabia, and several U.S. cities. The median VOC concentrations for benzene, toluene, ethyl-benzene, and the xylenes at the Kuwait and Saudi Arabian sites are comparable to concentrations in urban centers in the U.S. The levels of NO2, CO, SO2, H2S, and PAHs were lower than expected, given the magnitude of the fires, and did not exceed those seen in U.S. cities or the EPA standards where established.


NOTE: Toluene measurement for Los Angeles not available.

Figure 2.3--Median VOCs Comparisons: Kuwait, Saudi Arabia, and Selected U.S. Cities

High levels of airborne particulate matter (sand and soot) were observed at several monitoring sites. Analysis of the samples indicated that the particles were mostly sand-based materials; high levels of airborne sand particulates are typical for this region of the world (Kirkpatrick, 1997). Within the PM10 samples of particulate matter, levels of PAHs and toxic metals were low.

A small subset of the ambient air samples collected in Kuwait and Saudi Arabia were analyzed to determine particle-type class and particle-size distribution of the PM10 data. The assigned classes fell into the following main categories: earth crustal (silica-rich, e.g., quartz), calcium bearing (calcium-rich, e.g., dolomite, gypsum), salt particles, carbon rich (e.g., soot), and miscellaneous (USAEHA, 1992). Figure 2.4 shows the percentile composition of the particulate matter in the air of Kuwait and Saudi Arabia (USAEHA, 1992). Considering that the sand of the Arabian Peninsula is rich in calcium and silica, it indicates that most of the PM10 is of sand origin and that in Kuwait about 23 percent of the total PM10 mass was contributed by soot from the oil well fires.

SOURCES: Kirkpatrick, 1997; USAEHA, 1992.

Figure 2.4--Particulate Composition of Air Samples in Saudi Arabia and Kuwait

Figure 2.5 depicts the particle-size distribution in air samples from Kuwait and Saudi Arabia. The results from a small number of samples indicate a significant mass of particles in the PM10 range.

SOURCES: Kirkpatrick, 1997; USAEHA, 1992.

Figure 2.5--Particle Size Distribution, Kuwait and Saudi Arabia

USAEHA Industrial Hygiene Measurements, May-June

A team of industrial hygienists from USAEHA performed supplemental monitoring at various sites in Kuwait and Saudi Arabia from May 3 to June 17, 1991. The focus of this operation was to sample areas where DoD service members were working outdoors at possible worst-case locations within the oil fields next to Kuwait City. Measurements focused on Khobar Towers, where large numbers of troops awaited departure from the region through the ports of Dammam and Jubayl, and on Camp Thunderock in Kuwait City. At the time of this assessment, DoD personnel were neither working nor living in the vicinity of the oil fires. The workers in the oil fields were employees of fire fighting companies. These measurements are equivalent to personal sampling to determine occupational exposures while performing specific jobs or operations. The operations, all outdoors, included guard posts, supply points, equipment handling sites, ammunition handling and storage sites, and residential and field work locations.

The results are summarized in Table 2.9. The table provides means and standard deviations, maximums measured, and ACGIH's TLVs. Most measured pollutant concentrations were well below the occupational TLVs.

Table 2.9

Summary of Industrial Hygiene Air Sampling in Kuwait and Saudi Arabia

Pollutant Kuwaita Saudi Arabiaa Maximum Value ACGIH's TLVs
PM10 0.35 (0.64) 0.46 (0.24) 2.00 3.0
Coal Tar Pitch 0.06 (0.96) 0.10 (0.09) 0.21 0.2
Nitrogen Dioxide 1.65 (1.30) 0.40 (0.24) 6.70 5.6
Sulfur Dioxide 0.47 (0.72) 0.53 (0.65) 1.90 5.2
Nitric Acid 0.05 (0.02) 0.04 (0.05) 0.12 5.2
Sulfuric Acid 0.04 (0.01) 0.03 (0.01) 0.05 1.0
Benzene 0.04 (0.01) BDL 0.19 1.6
Toluene 0.13 (0.06) BDL 0.75 188
Xylene 0.37 (0.08) BDL 3.21 435


NOTES: amean (standard deviation). BDL: Below Detection Limit.

Table 2.10
Comparison of 1991 and 1993 Mean Contaminant Concentrations

Khobar Towers Camp Thunderock
Contaminant 1991 1993 1991 1993
Naphthalene 1.10 0.11 2.14 0.05
2-Methylnaphthalene 0.21 0.05 0.24 0.02
Dibenzofuran 0.17 0.004 0.13 NA
Fluorene 0.03 0.004 0.1 NA
Phenanthrene 0.04 0.008 0.02 0.02
PM10 62 52 84 44
Cadmium 0.001 0.0009 0.001 0.0002
Chromium 0.003 0.013 0.017 0.005
Nickel 0.02 0.007 0.05 0.02
Lead 0.29 0.35 0.26 0.1
Vanadium 0.005 0.005 0.007 0.005
Zinc 0.05 0.05 0.07 0.03
Benzene 4.5 3.4 10.6 1.2
Toluene 18.5 8.9 33.9 2.7
Ethyl Benzene 3.9 2.7 3.6 1.0
m,p-Xylene 11.3 6.1 18.8 2.7
o-Xylene 4.3 2.9 17.1 1.2

SOURCES: 1991 data: USAEHA, 1994; 1993 data: Kirkpatrick, 1997.

NOTE: NA = Not available.

Measurements Taken After the Oil Well Fires

The USAEHA conducted an additional monitoring effort in November 1993 in Camp Thunderock, Doha, Kuwait, and Khobar Towers, Dhahran, Saudi Arabia, to provide additional information on postfire air pollution levels. The mean concentrations of the contaminants of interests for Camp Thunderock and Khobar Towers measured during November 1991 and November 1993 are listed in Table 2.10. The 1993 campaign was a limited effort, and these means should be considered only as an indicator of air pollution levels.

The results indicate that the metals and VOC readings at Khobar Towers in 1993 were about the same as those in 1991, but PAH and PM10 levels were lower. The November 1991 VOC data for Khobar Towers are similar to the November 1993 levels, except for toluene. The Khobar Towers VOC levels are a factor of three higher than Camp Thunderock. The PAH levels detected in November 1993 were 2 to 8 times lower than in November 1991. For PM10 the November 1993 mean levels are lower than in November 1991, decreasing from a mean concentration of 62 µg/m3 to 52 µg/m3.

At Camp Thunderock, the readings for all four categories were substantially lower in 1993 than they were in 1991. The metal levels from November 1993 are a factor of 2 lower than those in November 1991. In the November 1993 PAH data, most of the compounds are below detection limit and the rest are about three times lower than those in November 1991. PM10 levels decrease from 84 µg/m3 to 44 µg/m3.


This chapter summarizes the available data on environmental contaminants measured in Kuwait and Saudi Arabia beginning when most of the oil wells were still burning and ending after the fires were extinguished. U.S. occupational guidelines for contaminants offer a practical standard against which to measure exposure levels experienced by U.S. troops. As discussed above, ACGIH standards are set for workplace exposures for 8-hour days and 40-hour weeks, or about 2000 hours per year for a typical working career of 40-45 years.

Table 2.11 displays the maximum or 95th-percentile concentrations in the air for the pollutants of concern as measured by the USAEHA from May to December 1991, and the ACGIH-recommended exposure limits for hazardous substances in the workplace. These results show that, except for ozone, the maximum concentrations for all pollutants in the Gulf were several orders of magnitude lower than ACGIH occupational standards. And ozone, which is ubiquitous in the U.S., was still lower than in many U.S. urban areas where summer episodes reach twice the NAAQS.

A possible objection to the above comparison is that U.S. personnel in the Gulf were being exposed to air pollution 168 hours per week for up to 70 weeks, while occupational exposures are spread over 40 hours per week during an adult working lifetime. Nevertheless, if the mean pollutant concentrations due to the Kuwait oil well fires are compared to the NAAQS and to the ATSDR's MRL levels, the Gulf levels were lower than the U.S. standards set for the general population (except for PM10), and lower than the daily exposures of millions living in major U.S. cities. However, PM10 levels, unrelated to the oil well fires, were much higher than ambient levels in the U.S., but within the ACGIH's TLV levels. Gulf War veterans, like people living in urban areas in the U.S., were exposed to multiple pollutants simultaneously for which there are no standards.

Table 2.11
Maximum, or 95th Percentile, Concentrations of Air Pollutants of Concern

Pollutant Sym Location ACGIH TLVs Maximum [C]a Maximum [C]b
Ozone O3 Camp Thunderock 100 µg/m3 104.8 µg/m3 (Kuwait City only)
Sulfur dioxide SO2 Ahmadi 5200 µg/m3 92.5 µg/m3 11.0 µg/m3
Nitrogen dioxide NO2 Khobar 5600 µg/m3 86.1 µg/m3
Nitric oxide NO Khobar 31,000 µg/m3 61.1 µg/m3
Acenaphthenec Eskan Village 200,000 ng/m3 2.25 ng/m3 > 1 ng/m3
Benzo(a)anthracenec Eskan Village 200,000 ng/m3 2.23 ng/m3 > 1 ng/m3
Biphenylc Eskan Village 200,000 ng/m3 19.07 ng/m3 > 1 ng/m3
Chrysenec Eskan Village 200,000 ng/m3 2.25 ng/m3 > 1 ng/m3
Fluoranthenec KKMC 200,000 ng/m3 2.23 ng/m3 > 1 ng/m3
Phenanthrenec Ahmadi 200,000 ng/m3 1.84 ng/m3 > 1 ng/m3
Pyrenec Eskan Village 200,000 ng/m3 3.54 ng/m3 > 1 ng/m3
Particulate PM10 U.S. Embassy 3000 µg/m3 1842 µg/m3
Cadmium Cd Camp 1 10 µg/m3 0.0078 µg/m3
Chromium Cr U.S. Embassy 500 µg/m3 0.0898 µg/m3 0.013 µg/m3
Lead Pb Eskan Village 50 µg/m3 1.596 µg/m3 1.671 µg/m3
Nickel Ni Camp 1 120 µg/m3 0.2136 µg/m3 0.0081 µg/m3
Vanadium V Camp 1 50 µg/m3 0.0898 µg/m3 0.0093 µg/m3
Zinc Zn Camp 1 500 µg/m3 0.193 µg/m3 0.172 µg/m3
Pollutant Sym Location ACGIH TLVs Maximum [C]a Maximum [C]b
Benzene Ahmadi 1600 µg/m3 13.1 µg/m3
Toluene Ahmadi 188,000 µg/m3 36.9 µg/m3
Ethyl benzene Ahmadi 435,000 µg/m3 41.2 µg/m3
m,p-Xylene Ahmadi 435,000 µg/m3 116 µg/m3
o-Xylene Ahmadi 435,000 µg/m3 30.4 µg/m3

aFor particulates, metals, and VOCs, this column gives the 95th percentile [C]; for PAHs and Criteria Pollutants it gives the maximum [C] (USAEHA, 1994).
bStevens et al., 1993.
cThere were only a few samples above the detection limit. The ACGIH TLV is for coal tar pitch volatiles.

[1]Total suspended particulate (TSP) is a historical term for airborne particles under about 30 mm. TSP has been replaced by the more precise and regulated parameter, PM10, i.e., particulate matter of <10 mm.

[2]The cut-off value of 3.5 mm, PM3.5, was arbitrarily set in the particle analyzer. These measurements were taken before the PM2.5 standard was promulgated and is the closest available data above PM2.5.

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